1. Technical Field
The present invention relates generally to backup of computer systems and, more particularly, but not by way of limitation, to backup of computer systems utilizing both physical media and network-transfer techniques.
2. History of Related Art
Computer software and data are often stored on disk drives. Since the disk drives and computers incorporating the disk drives can fail, copies of data files, application files, operating-system files, and user data files often must be backed up so that the files can be restored from backed-up file copies if need be. If the backed-up file copies are kept in a remote location, the backed-up file copies can be used to recover disk-drive information in case the disk drive or a computer that includes the disk drive is physically destroyed or otherwise becomes inoperable or unavailable. A process of copying data files, application files, operating-system files, and any other files located on a disk drive, and storing the copied files remotely, is referred to as computer backup. Computer backup may be used to create a disk image. For purposes of this patent application, the term disk image refers to a single file or storage device that contains the complete contents and structure representing a data-storage medium or device, such as, for example, a hard drive, floppy disk, CD, or DVD. A disk image is usually created by creating a complete sector-by-sector copy of a source medium and thereby perfectly replicating the structure and contents of the data-storage medium or device.
Computer backup has historically used external physical media to create a copy of the disk image or copies of files changed since the last time a backup was performed. The term incremental backup is used to refer to a backup of a plurality of backups that includes only those files that have been changed since the most-recent previous backup of any type. In contrast to an incremental backup, the term differential backup refers to a cumulative backup of all files that have been changed since the most-recent previous full backup. The term full backup refers to a backup of an entire data store, regardless of whether or not the data store has been changed since a most-recent previous backup was performed. A full backup results in a complete copy of all data in the data store; however, a full backup is often times consuming and can create many redundant backup files.
Tape media are often used in computer backup. When tape media are used, the tape media can then be transferred to a remote location for safe storage. Such a transfer process is known as tape vaulting. When used for computer backup, tape media has several advantages, including lower cost, increased capacity, and enhanced portability.
Computer networks have become widespread and offer another way to create and transport software and other data to a remote location. Because of the slow transfer speeds of wide area networks (WAN) versus tape media, which are often 2-3 orders of magnitude different, and the significant capital expenditure and operational costs of storing file copies directly on disk, online backup via network transfers has generally been limited to relatively small amounts of critical user data. Complete backup of a computer's hard-disk drive using only network transfers has not been feasible or economically practicable; therefore, network transfers are typically used to protect only a portion of software and other data on a computer. For this reason, a full backup that would permit a bare-metal restore is generally not possible using network-transfer techniques. The term bare-metal restore is used to refer to a technique in which backed-up data is available in a form that allows one to restore a computer system from bare metal, the term bare metal meaning without any requirements as to previously installed software or operating system. In addition, a disk image of a hard drive cannot generally be constructed using purely online backup techniques because certain information such as disk partitions and other non-file-based information required to generate the disk image are often not found in a full backup and also because disk images are very large and transferring them purely over the network is too slow.
Full backup of a computer over WAN has not to date been practical due to rapid data-storage-capacity increases of hard-disk drives compared to bandwidth available on a WAN. Hard-disk drive capacities have been increasing at an annual rate of approximately 100%, which increases have widely outstripped WAN bandwidth increases. For example, typical current hard-disk drives have a data capacity of 1 Terabyte (TB) or more. To transfer 1 TB of data via a 50 kilobyte/second (KB/s) internet upload in a typical U.S. home would take approximately 232 days. Though large corporations often purchase and utilize network connections with much greater bandwidths on private WANs, this bandwidth is very expensive. In addition, corporations that can afford this amount of bandwidth generally have very large amounts of data to back up daily, such as 10's of TB per day).
For purposes of this patent application, a remote computer is a computer that is physically external to a physical computer network. A typical remote computer is a desktop personal computer (PC) located at the home of a corporate employee. A mobile computer is a computer that can change physical location and IP address and can therefore under certain conditions be a remote computer. A remote computer is often referred to as being in the field.
Typical mobile computers include smart phones, personal digital assistants (PDAs), notebook computers, netbook computers, other portable devices capable of accessing the internet via for example, other WIFI or wireless local-area-network connection, and the like. In contrast to mobile computers, a remote computer that is not a mobile computer typically remains in the same physical location and on the same IP subnet.
Management of mobile computers and remote computers poses many problems. Since remote computers and mobile computers are often only infrequently connected to the corporate network, and system-management tasks must generally be executed on systems that reside on a corporate network, execution of the system-management tasks often involves a set of manual, complex, tedious processes across a plurality of separate software packages. A major challenge is consistently executing the system-management tasks on remote computers and on mobile computers that are intermittently connected to a physical network, such as those a corporate network.
Some typical system-management tasks are listed below.
Backup operations on applications, operating-system software, and user data on a mobile computer or remote computer.
Recovering data from, for example, failed hard-disk drives, when no backup is available. In this case, the hard-disk drive must typically be shipped to a data-recovery service such as ONTRACK. The data-recovery services are often expensive and time-consuming and may not recover all data under all circumstances.
Restoring specific files or a complete current backup disk image to a computer.
Installing an operating-system-software image and software applications.
Tracking license usage for software deployed and used on remote computers and mobile computers.
Upgrading software on mobile computers and remote computers in the field.
Tracking license usage for upgraded software on mobile computers and remote computers.
Detection and removal of viruses and other malware, disk tuning and disk de-fragmentation, software tuning, incremental software updates, detection and deletion of sensitive files that are deemed to be impermissible to be stored on a particular mobile computer or remote computer. Examples of files that could be deemed impermissible to be stored on a particular mobile computer or remote computer include files, for example, that: 1) contain objectionable material such as pornography; 2) are unauthorized versions of copyrighted material; 3) contain corporate confidential information such as trade secrets, Board meeting minutes, layoff notices, personnel files or reviews; and 4) contain consumer-related or customer-related private information that, if released outside the corporation, would require the declaration of a data breach.
Migration from old to new mobile-computer or remote-computer hardware that requires migration of existing operating-system software, applications, and user data, and installation of drivers to support the new mobile-computer or remote-computer hardware and any associated devices.
On remote computers and mobile computers, tracking, decommissioning, and properly accounting for inactive software licenses, physical asset decommissioning, and assuring destruction of all corporate files. In particular, mobile-computer software and license inventory are often difficult to manage across a corporate inventory of mobile computers and remote computers.
Disabling mobile computers or remote computers and removing sensitive and corporate files when necessary, including cases where a remote computer or mobile computer is lost or stolen, or the remote computer or mobile computer is no longer being used for corporate purposes, such as use by a former employee.
Performing information-security tasks on mobile computers and remote computers. For example, some data files may contain sensitive corporate information, illegal data files such as unauthorized copies of copyrighted material, objectionable material such as pornography, or perhaps worst of all, private customer information. In the latter case, if the private customer information, such as, for example, social security numbers, credit-card numbers, or health information, is on a mobile computer that is stolen or lost, the private customer information must often be considered under applicable law to have been lost and a data breach declared. Several states now require that consumers be informed in the case of a data breach. Expensive litigation and complex expensive processes to track down and inform consumers of a data breach can cost millions of dollars and significantly impact a corporation's stock value.